Introduce Type::IsCurrently

src/types.cc

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 226 matching lines @@
   } else if (this->is_union()) {
     // All but the first are non-bitsets and thus would yield kNone anyway.
     return union_get(this->as_union(), 0)->GlbBitset();
   } else {
     return kNone;
   }
 }
 
 
 // Most precise _current_ type of a value (usually its class).
-Type* Type::CurrentOf(Handle<i::Object> value) {
+Type* Type::OfCurrently(Handle<i::Object> value) {
   if (value->IsSmi()) return Smi();
   i::Map* map = i::HeapObject::cast(*value)->map();
   if (map->instance_type() == HEAP_NUMBER_TYPE ||
       map->instance_type() == ODDBALL_TYPE) {
     return Type::Of(value);
   }
   return Class(i::handle(map));
 }
 
 
@@ skipping 32 matching lines @@
       if (this->Is(that_i)) return true;
       if (this->is_bitset()) break;  // Fast fail, no other field is a bitset.
     }
     return false;
   }
 
   return false;
 }
 
 
+bool Type::IsCurrently(Type* that) {
+  return this->Is(that) ||
+      (this->is_constant() && that->is_class() &&
+       this->as_constant()->IsHeapObject() &&
+       i::HeapObject::cast(*this->as_constant())->map() == *that->as_class());
+}
+
+
 // Check this overlaps that.
 bool Type::Maybe(Type* that) {
   // Fast path for bitsets.
   if (this->is_bitset()) {
     return (this->as_bitset() & that->LubBitset()) != 0;
   }
   if (that->is_bitset()) {
     return (this->LubBitset() & that->as_bitset()) != 0;
   }
 
@@ skipping 260 matching lines @@
       if (i > 0) PrintF(out, " | ");
       type_i->TypePrint(out);
     }
     PrintF(out, ")");
   }
 }
 #endif
 
 
 } }  // namespace v8::internal